Watercraft

ABSTRACT

A multipurpose watercraft having spaced bouyant foam-filled pontoons with wide flat bottoms, laterally extending longitudinal stabilizing flanges, and supporting therebetween an open suspended cockpit mid-hull with rear sloping bottom and spaced corner self-bailers spaced above the normal flotation waterline of the craft. A mast is removably inserted in a laterally reinforced mast socket disposed beneath and connecting through a seat in the cockpit.

[22] Filed:

llnited States Patent 1 91 .Critcher 41 WATERCRAFT v 75] Inventor: JohnL. Critcher, Cockeysville, Md.

73] Assignee: Reginald F. Pippin, ,In, a part interest Aug. 3, 1970 [21]Appl. No.: 60,351

52 Us. (:1. ..114/61, 9/6, 114/05 F,

114/435 511 161.01 ..B63b 3/00, B636 35/00 58 Field Of Search ..1 14/61,43.5, 66.5 F, 114/05 F, 185, 140, 44, '45, 39; 9/3, 7

[56] References Cited UNITED STATES PATENTS- 2,704,529 3/1955 116166,;..114/61 x 2,884,883 5/1959 Pujol ..114/185 674,597 5/1901 Buckel ..9/4A 3,065,724 11/1962 Tritt..; ..114/219X 1451 Apr. 10, 1073 3,126,8553/1964 Freeburg ....1 14/45 2,375,973 5/1945 Cooper et a1 3,403,652 10/1968 Hardy 3,448,712 6/1969 Lehmann et a1 3,115,860 12/1963 Payne ..114/66.5 F

FOREIGN PATENTS OR APPLICATIONS 255,246 7/1926 Great Britain ..1 l4/66.5F

Primary Exaininer-Trygve M. Blix A homey-Reginald F. Pippin, Jr.

[ ABSTRACT A multipurpose watercraft having spaced bouyant foam-filledpontoons with wide flat bottoms, laterally extending longitudinalstabilizing flanges, and supporting therebetween an open suspendedcockpit mid-hull with rear sloping bottom and spaced comer selfbailersspaced above the normal flotation waterline of the craft. A mast isremovably inserted in a laterally reinforced mast socket disposedbeneath and connecting through a seat in the cockpit.

22 Claims, 22 Drawing Figures PATENTED 1 @1973 3.726245 sum 2 [1F 7'Inventor:

PATENTEU 3.726.245

sum 3 OF 7 In ven for:

PATENTEU 3.726245 SHEET l 0F 7 fnvenfor:

(/a/m/ z. m fw/z/z PATENTED 1 01975 3. 726 245 sum 5 UF 7 InventorPATENTEDAFR101973 3.726.245

SHEET 5 OF 7 [r2 verifor PATENTEDAPRIOIGYS 3 726,245

SHEET 7 OF 7 WATERCRAFT This invention relates to a twin pontoonwatercraft which has multipurpose capability, including sailing, poweredski towing, and rowing, and which possesses substantial lateralstability as well as a gravity action self-bailing arrangement.

It is a feature of the invention to provide a novel selfbailingcatamaran watercraft.

A further feature is the provision of a watercraft which has simple yetrugged and stable construction for economy of manufacture.

Still a further feature is the provision of a catamaran watercraft withimproved lateral stabilizing shallow draft'pontoons.

Another feature is the provision of a catamaran watercraft havingprovision for mounting an outboard engine while minimizing propellerspray entry into the cockpit.

A still further feature is the provision of a pontoon watercraft, thepontoons of which are sufficiently efficient and laterally stable toenable both reasonable sailing efficiency and lateral stability, andpowered planing efficiency.

Still further features and attendant advantages will become apparent toone skilled in the art from a reading of the following detaileddescription of an embodiment of the invention, taken in conjunction withthe accompanying drawings, wherein:

FIGS. 1 and 2 are respectively rear and front perspective views of awatercraft according to the invention, and showing in phantom a typicalsail attachment.

FIG. 3 is a plan view of the embodiment of FIGS. 1

and 2, with sail removed.

FIG. 4 is a section view taken on line 4-4 of FIG. 3.

FIG. 4a is a fragmentary section view illustrating the cross braceconnector assembly.

FIG. 5 is a front elevation view of the embodiment, minus sails.

FIG. 6 is a section view taken along line 6-6 of FIG. 3.

FIG. 7 is an enlarged fragmentary longitudinal section view showing oneof the two gravity-flow selfbailers.

FIG. 8 is a section view taken on line 8-8 of FIG. 7.

FIG. 9 is a partially exploded perspective view of the watercraft,showing the pontoon and cross-brace connector assembly separated fromthe mid-hull cockpit, with one pontoon illustrated in phantom to betterillustrate the interior rigidifying framework of the pontoons.

FIG. 10 is a fragmentary section view, partially in phantom,illustrating the pontoon framework and midhull-to-pontoon connectionsand mast support structure.

FIG. 1 1 is a fragmentary section view-showing the at- I tachment ofperipheral rubber bumper to the pontoon and cross brace connectorassembly.

FIG. 12 is a fragmentary view illustrating the releasable detentsecuring arrangement for the removable rear center seat section.

FIGS. 13 and 14 are schematic rear view in partial section of twomodified constructions.

FIGS. 15 and 16 are schematic illustrations of the spray deflectionproblem and the spray deflection action by the spray deflector.

FIGS. 17 through 20 are schematic functional stability comparison viewsof the shallow draft catamaran pontoon arrangement according to oneaspect of the present invention relative to a conventional deeper draftcatamaran pontoon arrangement.

FIG. 21 is a schematic illustration of the lateral motion stabilizingaction of the flanged pontoon arrangement.

Referring now in detail to the figures of the drawings, FIGS. 1 and 2illustrate one physical embodiment of the invention, with sail attached,and the remaining figures having the sail removed for clarity ofillustration, as the sail is one of several featured modes ofutilization. In the illustrative embodiment the invention takes the formof a twin pontoon catamaran watercraft 11, including two identicalmirror image pontoons 13 spaced laterally apart and inter-connectedthrough the medium of a front cross-brace connector 61 and a rearcross-brace connector 71 suitably secured thereto,

preferably by welding. Secured in raised suspended position between thetwo pontoons 13 is a mid-hull cockpit 33 which may be employed forpersonnel and cargo carrying.

As is indicated in the figures, particularly FIG. 4, each of thecross-brace connectors 61 and 71 and the bottom of the mid-hull cockpit33 is disposed substantially above the normal flotation waterline of thetotal watercraft 11, thereby contributing to the efficiency of thewater-craft in the water and providing a central clear water flow pathbetween the two pontoons.

In addition, the disposition of the mid-hull cockpit 33 substantiallyabove the normal flotation waterline of the craft ll enables theadvantageous provision according to the invention of a uniqueself-bailing arrangement, whereby any water finding its way into thecockpit 33 will be drained by gravity from the cockpit, independent ofwhether the craft 11 is in motion or not. To this end, the cockpit 33has its bottom 35 tilted or slanted downwardly and rearwardly along itsentire length from fore to aft, and is advantageously flat over itsmajor surface area. This rearwardly slanted disposition of the cockpitfloor or deck 35 is maintained in the quiescent state of the craft 11 byfixing this tilt of the cockpit 33 in this respect relative to thenormal flotation waterline of the pontoons 13 under the self-loadedcondition as a total watercraft 11. Thus, as shown in FIG. 4, the majorand rear area of the mid-hull cockpit bottom 35 is maintained in anormal quiescent position at a tilt angle as indicated by the letter A,and for this and other purposes the further most forward portion of thedeck 35 of the cockpit 33 is tilted at this or a greater angle relativeto the normal flotation waterline, and the forward nose wall 41b of thecockpit 33 is tilted at a still greater angle. By so providing acontinuous fore to aft slant of the deck 35, it will be seen that waterentering the cockpit will flow toward and into the rear section of theboat, unless impeded by interior obstacles.

The water accumulating at the rear of the cockpit 33 by gravity flowalong the downwardly and rearwardly slanted deck 35 thereof is normallycontinuously discharged by gravity flow through two self-bailers 101.The two self-bailers are disposed at opposite lateral corners of thecockpit and on the rear transom wall of wall 41a, each having an orifice103, the entrance of which is level with the deck and at or closelyadjacent a respective rear corner. In addition, the self-bailers 101 areeach provided with a check valve, which may take various suitable forms,the illustrative example being formed as a single tube extension 105with a free check flotation ball 107 disposed therein and retained inplace by a cross pin 109.

It will be noted from FIG. 4 that the self-bailers 101 are disposedabove the normal waterline of the craft 11, including both the entranceorifice 103 and the zone of the check ball 107, thereby enabling thecontinuous gravity discharge of water from the cockpit 33 through one orboth of the corner self-bailers 101, without requirement for craftmotion. It will also be appreciated that by providing the self-bailers101 at the opposite corners of the cockpit, the deck 35 is enabled to besubstantially flat, which is a desired configuration for personnelcomfort and maneuverability. Thus, with the flat deck 35 of the cockpit33, it will be appreciated that the water will drain out from thecockpit through one or both of the self-bailers 101 irrespective of thelateral tilt or non-tilt of the craft 11, although of course there maybe moments when forward, downward tilting of the craft will preventrearward water flow along the deck 35, as it is not desirable to providesuch a very large slant to the deck 35 as to always maintain rearwardslanting under all sea states, such as in heavy seas. A relativelyshallow angle, of for instance 50, is quite adequate for the presentpurpose, while still providing comfortable personnel maneuverability andfooting on the deck 35.

In view of the desirability of the deck 35 being as flat as possible forpersonnel comfort and maneuverability thereabout, the illustratedembodiment is highly preferred. However, it will be appreciated that theselfbailing may be effected with less desirable arrangements, whilestill providing the continuous gravity-flow self-bailing characteristicswhich are effected by the basic configuration of dual pontoons carryinga midhull cockpit with its bottom deck disposed above the normalflotation waterline of the craft, and with gravity self-bailers at thelow point or points of the cockpit bottom deck. For instance, the bottomdeck 35 may be slightly crowned or form a slight inverted V, with thecrown or apex extending along the centerline of the deck 35 asillustrated in FIG. 14, and with the deck 35 also rearwardly slanteddownwardly and with similar corner self-bailers 101 provided in the reartransom wall, as in FIG. 1. Alternatively, and substantially lessdesirable, is the provision of a single self-bailer in conjunction witha slight V-sloped deck 35, also rearwardly slanted downwardly, and withthe self-bailer 101 disposed in the rear transom wall, as shownschematically in FIG. 13.

As shown in FIG. 7, it will be appreciated that while check ball 107will normally enable free flow gravity passage of the water from thedeck 35 through the apperture 103, inasmuch as the ball 107 issubstantially above the normal water flotation waterline and is therebyresting against the support pin 109, the canting of the boat in heavysea state conditions, or by the wash of a wave against the rear wall 41aof the cockpit, will result in the check ball 107 bouyantly rising, asthe check ball 107 is of buoyant, preferably hollow, con struction, suchas of plastic or rubber material, and the rising of the check ball 107within the stepped-down diameter upper mid-zone section of tube and thesealing thereof against the reduced diameter mouth 105a willsubstantially effectively close the discharge orifice 103 to therebyprevent undesired entry of water past the check ball 107 into thecockpit 33. Upon the removal of the upward water pressure by thesubsequent lowering of the water level relative to the cockpit 33 andself-bailer 101, the check ball 107 will again freely return undergravity action to its lowermost position against the retaining pin 109,thereby permitting any accumulated water in the cockpit 33 to freelyflow out through one or both of the orifices 103 of the two self-bailers101, depending on the instant craft attitude.

The self-bailer discharge tubes 105 are canted rearwardly anddownwardly, and have a generally horizontal discharge mouthconfiguration, thereby further aiding in assuring water exittherethrough during forward motion when water flow or wave action mightresult in relative motion of the self-bailers forwardly through aquantity of water or spray. It will also be apparent that during suchrelative forward motion any rearward passage of water past and in totalcontact with the discharge tube 105 will result in venturi dischargesuction assist for the self-bailers, in addition to the normal otherwisegravity flow discharge action therethrough due to the normal verticalsuspension of the mid-hull 33 and self-bailers 101 above the normalflotation waterline of the craft 1 1.

In order to provide a desired flow path from front to rear, the seats 37and 39 in the cockpit 33 are provided with supports which enable theeffective flow of water therepast along the bottom deck 35. In thisrespect, the rear seat 39 is provided with knee brace supports 39b whichmay be suitably secured respectively to the seat 39 and the cockpit deck35, as by welding, riveting, or the like. In addition, the seat 39 ispreferably secured at its respective ends to the upstanding outwardlytilted side walls 41 of the cockpit 33. The rear seat alsoadvantageously is provided with a removable center section 39a, in orderto enable the mounting of both small and large size motors on thetransom 41a of the cockpit 33. Normally, small size motors will notrequire the removal of the center seat section 390.

The removable rear center seat section 39a may be suitably removablysecured in place to the respective adjoining side rear seat sections, asthrough the medium of releasable detent pins 39c, as illustrated forinstance in the fragmentary exploded view of FIG. 12. These releasabledetent pins 390 may be spaced at suitable positions, as may be desiredfor adequate securing purposes, the pins being releasably engageablewith corresponding complementary apertures 39g in an adjoining wallsection of the respective side seat portions.

The center and forwardmost seat 37 serves the dual purpose of providinga seating surface as well as providing a mast support socket, asindicated at 37a. Thus, a sail 53 may be suitably mounted on a main mast53a with boom 53b, by insertion of the main mast into the mast socket370, and the mast may then be secured in place as by a mast lock pin53c. Further or different sails may be provided as may be desired,including for instance a job sail 55, and/or spinnaker (not shown),

and fore-stay and aft-stay lines 57 may be secured to securing eyes 59provided on the upper surface of the front and rear cross-braceconnectors 61, 71, and at the ends of the pontoons 13.

Further cross bracing of the combined seat and mast socket 37,37a isprovided in the form of an undersupport platform therefor, includingforward and rear box beams 37b and 37h, which are secured as by weldingat their opposite lateral ends to the upstanding side walls 41 of thecockpit, and are likewise secured at spaced positions therealong to thedeck by spacers 37c, providing floor or deck drain passageways 37dtherebetween. A lateral Y-brace is formed with the mast socket tube 37aat its center, and includes two rearwardly angled vertical plate braces37g and a longitudinal vertical plate brace 37j, each of which issuitably secured, as by welding, to the mask socket tube-and theadjoining section of the respective box beams 37b and 37h. In addition,the seat 37 is secured to the mast socket tube 37a and is welded at itsopposite ends to the side walls 41 of the cockpit, thereby furtherbracing the mast socket. Further lateral bracing is effected byutilization of further angle braces 37e, and the mast socket 370 iseffectively bottomed by further generally horizontal brace plate 37fwhich is likewise welded or otherwise suitably secured to the adjoiningcross bracing members of the seat/mast socket arrangement.

The mast socket tube may suitably have formed thereintransverse anchorpin apertures 37a, and the brace 37j may accordingly have a notch cuttherein to enable the mast anchor pin 53c to be readily removablyinserted through apertures 37a.

The rear box beam 37h is preferably formed with window openings 37h toenable the space beneath the seat to be used also as a storage area, ifso desired. A false bottom plate (not shown) may be suitably securedbetween box beams 37b and 37h and spaced above the deck 35 to enablewater-free storage beneath the seat 37, yet still permit free rearwardwater passage for full self-bailing discharge.

The box beams 37b and 37h serve a further additional function, ofproviding lateral bracing for securing of the cockpit 33 to the pontoons13. To this end, the cockpit 33 is secured to the pontoons through themedium of securing bolts or screws 91 which extend through the oppositeends of the box beams 37b, 37h and the side walls 41 of the cockpit, aswell as through the inner lateral skin 270 of the pontoon, beingthreadingly anchored in relatively thick anchor or tie plates 27d whichare suitably welded at aligned spaced positions on the internally innersurfaces of the pontoon skin 27c. The securing of the cockpit 33 to thepontoons 13 is effected in the foregoing manner at the center andforward end of the cockpit 33, and similar securing of the cockpit tothe pontoons 13 is effected at the rear of the cockpit by passage of ofsecuring screws 91 through the side walls 41 of the cockpit and intosimilar anchor or tie plates 27d in the pontoons. In order to economizeon material and weight, the rear wall or transom 41a of the cockpitserves as an effective lateral cross brace, by effecting the securing ofthe cockpit to the pontoons through screw or bolt holes located closelyadjacent the rear transom wall 41a.

As a particular aid to insuring ease of passage through heavy sea stateconditions of the supporting water surface, the craft is provided withforward and rearward effectively open spaces F0 and R0 between theforward and aft ends of the cockpit 33 and respective forward and aftcross-brace connectors 61 and 71 respectively. If desired for addedpersonnel room and/or ease of personnel movement over the craft, anopen-work grating or apertured deck may be secured, preferablyremovably, over the open spaces F0 and R0, with some reduction in waterpassage in this zone but with some compensating advantages by way ofadded effective deck space.

The lower surfaces 61a and 71a of cross brace connectors 61 and 71 arerespectively downwardly and in-- wardly oppositely inclined, as shown inFIG. 4 and 4a particularly, thereby aiding in providing bouyant raisingof the respective forward or rearward ends of the craft 11 upon theencountering from the front or rearward end thereof of a heavy wave formwhich may strike the forward or aft sections of the craft respectively.In addition, the forward and rearward bottom ends, 13f and 13rrespectively, of the pontoons are similarly inclined to provide forsimilar bouyant raising of the forward or rearward respective sectionsof the craft upon the encountering of an upward wave form, it beingnoted in this respect that the pontoons extend a substantial distanceforwardly and rearwardly of the cockpit 33, thereby effectively tendingto anticipate and raise the craft in the required forward or rearwardzones prior to encountering of a wave by the adjacent forward orrearward sections of the cockpit 33, the front and rear cross braceconnectors 61 and 71 likewise functioning in this respect, although onlyunder relatively severe wave form action such as to strike the lowersurfaces 610 or 71a thereof before effective raising of the pontoons 13has occurred.

The pontoons 13 are effectively longitudinally and transversely crossbraced through the medium of an internal lightweight, yet high instrength, structurally braced network, including a plurality oflongitudinally spaced T-braces, each formed of a cross angle brace 21and a vertical angle brace 23 secured together as by welding, and eachof the spaced T-braces being intersecured in a single unit through themedium of a longitudinal vertically on-edge strip brace 25 also securedto one or both of the angle braces 21 and 23 of each of the T-braces, asby welding. The longitudinal strip brace is likewise suitably welded orotherwise secured to an end connector.26at each of its longitudinalends, which end connectors 26 are in turn welded, or otherwise suitablysecured, to the respective end wall skins 27g of the pontoons 13 asshown in FIG. 4a, such end connectors 26 being of relatively thickmaterial of substantial strength so as to serve as anchors for anchorbolts or screws 26a which are employed to secure the cross braceconnectors 61 and 71 to the respective pontoons 13. In this respect, thecross brace connectors 61- and 71 may also, or alternatively be, weldedto the pontoons 13 to provide a desired degree of unitaryinter-connection strength and a smooth crack-free surface joint,although the presently illustrated bolt-connected separably intersecuredpontoon and cross-brace connector arrangement is preferred for ease ofparts replacement, as may be required.

The T-braces 21,23 are suitably secured to the skin 27 forming the outerwalls of the respective pontoons 13, preferably by welding at theirjunction zones, and in this respect welding may be effected at only theupper end of the vertical angle braces 23 and the two opposite ends ofthe transverse angle braces 21. It is not necessary to weld the lowerend of the vertical angle braces 23 to the skin 27a forming the bottomof the pontoons l3, and this is an aid in enabling the assembly of thepontoons, as the entire bottom pontoon skin 27a may be added and securedin place after otherwise assembling the internal bracing and theremaining portion of the skin 27b, 270 to the internal bracing 21,23 and25. The bottom skin 27a may be suitably secured to the remaining skin27b, 27c by welding of lower side bend flanges 27b and 27c to lateralextensions 27a of the bottom skin 27a.

The inter-secured flanges 27a,27b thus form laterally extending sidestabilization flanges 13a for lateral stabilization of the pontoons l3,and consequently the entire craft 11, within the water, as will bediscussed hereinafter. In this respect, additional laterally extendingside flanges may be formed, if so desired, on the skin surfaces 27b and27c, as by welding or other desired securing to provide further lateralstabilization as may be required or desired. Such additional sideflanges are desirably normally below the normal waterline of thepontoons 13, but may also lie above the waterline so as to come intoaction only under heavy lateral sea state conditions or when otherstrong lateral motion forces that are encountered under other sea statesresulting in heavy lateral movement of water relative to the pontoons 13or vice versa.

While the pontoons 13 may be employed in hollow construction with onlythe internal bracing as described, and for light duty action withoutsuch bracing, it is highly desirable to provide flotation foamtherewithin, about and between the bracing 21-25. To this end, the skin27b may be provided along its upper surface with spaced filling holesfor filling of the interior of the pontoons with suitable flotation foammaterial which may thereby be foamed in place, after which fill plugs 29of suitable construction, such as self-locking plastic plugs, may besecured in place. In this respect, the pontoons are preferably providedwith a fill opening and fill plug 29 for each sequential longitudinalzone disposed between the sequentially spaced T- braces 21,23. It willalso be noted that the T-brace construction enables relatively free flowof flotation forming foam liquid between the zones, to insure adequateand full equalization and filling of the total pontoon interior.

In addition to the laterally extending side stabilization flanges 13afor lateral stabilization of the craft '11, the pontoons 13 also havesecured thereto, as by welding, longitudinal T-strip keel flanges 1312along the undersurface of the pontoon skin 27a. These T-strip keelflanges 13b are generally longitudinally vertically aligned with thevertical angle braces 23 of the internal rigidifying bracing 21-25, andaccordingly afford material additional strength to the pontoons, particularly in those instances where the entire craft may be supported on theT-strip keel flanges 13b, as where the craft may be supported on a hardsurface outside the water. In addition, the high strength constructionof the T-strip keel flanges and pontoon inner T-brace framework enablesthe T-strip keel flanges to be utilized for connection thereto of anunderlying hydrofoil arrangement, which may suitably be a hydrofoil (notshown) extending in common between and beneath the two pontoons, andsecured thereto as by bolts extending through holes 13b at spacedpositions along the T- strip keel flanges.

Each of the T-strip keel flanges 13b desirably extends not only alongthe flat bottom surface skin 27a of the respective pontoon 13, but alsoalong the forward slanted bottom surface skin at the forward end of thecraft, and while such may be also provided along the rear slanted bottomsurface skin, such does not normally come into substantial effectivekeeling action to the extent that the provision of the T-strip keelflanges aids in this respect on the forward slanted bottom surface skin.

The lateral stabilizing action of the laterally extending lateralstabilization flanges 13a, as well as the vertical T-strip keel flange13b for each pontoon 13 is schematically illustrated in FIG. 21. As willbe seen from this figure, relative lateral motion between the pontoon 13and the water will necessitate side flow displacement of the waterimmediately adjacent the lateral sides of the pontoon, thereby requiringthe water on the side facing the direction of motion of the pontoon toflow laterally downwardly and/or longitudinally and around the pontoonedges. Lateral downward motion of the water during this displacementwill require the water to pass in a horizontally transverse reverse-flowcourse toward itself around the respective bottom lateral stabilizationflange 13a, thereby providing an ef fective lateral stabilizingresisting action to motion of the pontoon l3 laterally in the water. Aswill be seen from this figure, lateral displacement of the pontoon 13will likewise require the usual vertical keel water displacement aboutthe vertical T-strip keel flange 13b, although it will also be seen thatthe substantially more restrictive and resistive lateral reverse flow ofthe water is not required in this respect. If so desired, furtherlateral resistive action may also be effected by forming the T-stripkeel flange 13b as l-strip keel flanges, although this will not normallybe required. In addition, further additional laterally extending lateralstabilization parallel longitudinal side flanges similar to flanges 13amay be, provided, as by welding, on the upper side wall surfaces of thepontoons 13, preferably beneath the normal flotation waterline of thepontoons, as heretofore noted. However, such laterally extending sidestabilization flanges may also be formed above the normal waterline asnoted heretofore, in which instance higher sea state conditions orgreater lateral motion forces may bring such lateral stabilizationflanges into operation. In this respect, the elastic peripheral bumperflange 17 may and does also serve as an effective high sea state lateralstabilization flange, in addition to its usual bumper function.

It will be apparent that the lateral stabilization flanges 13a and thevertical T-strip keel flanges present a relatively low forwarddirectional profile, thereby adding very little drag to the forwardmotion of the craft. In addition, as will be apparent, suchstabilization flanges add materially to the structural rigidity of thepontoons 13. In this respect, further structural rigidity is added tothe cockpit 33 through the medium of longitudinal parallel strip flangebraces 36 secured, as by welding, at spaced lateral positions across thewidth of the undersurface of the deck 35. These longitudinally extendingrigidifying strip flange braces 36 also present a relatively smallforward profile, being parallel with the longitudinal axis of thewatercraft 11, and also normally present no direct water drag on forwardmotion of the craft under calm sea state conditions inasmuch as they arenormally disposed above the waterline in view of the verticallysuspended and disposition of the cockpit 33 above the waterline on whichthey are formed. If so desired, these longitudinal strip flanges 36 mayalso be formed as T-strip flanges or I-strip flanges, thereby providingadditional structural rigidity and further aiding in lateral stabilizingaction against high sea states, although it will be apparent that theillustrated construction of the rigidifying longitudinal strip flanges36 also serves as an important aid in lateral stabilization undergreater sea states. In connection with the rigidifying action of thedownwardly depending longitudinally extending strip flanges 36, it willbe noted that this exterior rigidifying construction enables theinternal deck surface to be smooth and unencumbered, while affordingsufficient rigidity to the craft cockpit deck 35. In further rigidifyingthe cockpit 33, the gunwhale 43 is formed in the illustrated embodimentas a peripheral rounded or flat lip of substantial width, thissubstantial width also providing for personnel comfort in affordingadditional seating space. In addition, the forward end section 43a ofthe gunwhale is of even wider width, and further aids in reducing thelikelihood of water entering the cockpit during forward motion or underheavy sea states.

The craft is, as has been heretofore noted, capable of utilization invarious modes, including both sailing and/or with power assist or powerpropulsion, as through the medium of an outboard motor M. In thisrespect, as illustrated schematically in FIG. 15, there is somepossibility and likelihood of spray deflection from the propeller P ontothe rear cross brace connector 71 and back into the cockpit 33. Thespray action may also be sometimes present in other forward motionconditions, as with sails when the vesselis tilted heavily to one side.As an aid to alleviating this difficulty, and also for the purpose ofproviding a more efficient water passage configuration, the watercraftis provided with a spray deflector 81 which is downwardly and rearwardlyinclined on its undersurface and is disposed rearwardly of the cockpit33 and in front of the rear cross brace connector 71. In a preferredembodiment of this spray deflector 81, the deflector takes the form of aplate having drain apertures 81a formed therein at spaced intervalsacross its width and at or near its bottom end, and this spray deflectorplate is preferably pivotably mounted for tilting upwardly and out ofthe way, particularly when the motor M is required to be attached orupwardly tilted for travel, as on a trailer or for other mounting of thecraft 11 out of the water and on a hard supporting forward surface. Tothis end, the spray deflector plate 81 is advantageously pivotallymounted at its lower end as by a transverse hinge or hinges secured tothe lower forward end portion of the cross brace connector 71. Water mayalso drain out through and past the securing hingeor hinges 81b. Theresulting passage of the water into contact with the spray deflectorplate 81 substantially alleviates the problem of spray entering from therear into the cockpit as a result of otherwise striking the rearcross'brace connector 71. Selectively releasable securing of the spraydeflector 81 in operating position, as shown, may be readily effected byprovision of a spring biased releasable detent pin 83 which mayreleasably slidably fit into an anchor plate aperture formed on the sidewall of the pontoon skin adjacent the spray deflection plate 81, asillustrated generally in FIGS. 3 and 9.

The multipurpose catamaran watercraft 11 is particularly advantageous,not only as a sail craft, but also as a motor powered craft forrelatively efficient planing travel along the water. To this end, thepontoons 13 are formed with substantially flat bottom surfaces, as notedheretofore, having substantially flat upwardly inclined front and rearends thereof. In addition, the pontoons 13 are formed with relativelywide cross sectional shape, and their wide cross sectional shape ispreferably formed to provide a very shallow draft for p the totalwatercraft 11. Thus, as illustrated in FIGS. 19

and 20, the cross sectional area of displacement 13R in the normalquiescient condition of the craft is rectangular, with the long side ofthe displacement rectangle horizontal, and the short side of therectangle vertical.

This is quite different from the conventional catamaran construction asillustrated in FIGS. 17 and 18, in which the pontoons P are relativelynarrow and have a deeper draft than their width. This basic differencein pontoon configuration serves several purposes in the presentinvention, including decreased drag and better ability to plane, as wellas greater return torque moment stabilization in the transversedirection. This latter transverse stabilization characteristic isillustrated in FIG. 20 as compared to the deeper draft catamaranconstruction as illustrated in FIG. 1Q. Thus, for a given angle of tiltof the craft 11 transversely, as for instance to a point where one ofthe pontoons 13 is at the surface of the water, the return torque couplewill be F -L whereas with the same angle of transverse tilting for thedeeper draft vessel, the return torque couple will be (F A-L A)(F A-LThus, the effective restoring torque arm L and the effectivedifferential restoring torque force F is greater for a given angle oftransverse tilt of the watercraft, thereby affording substantiallyincreased lateral stability to the craft. In addition, the side flangestrips 13a tend to reduce the transverse tilting motion of the craftabout the center of gravity, as such side flange strips resist thepassage of water there past in the vertical plane, as will be readilyapparent.

The elastic peripheral bumper is advantageously secured, as by securingscrews 17a in a groove formed as by interfacing angle strips welded tothe pontoons 13, and by similar screws 17a" in spaced securing lips onthe front and rear cross brace connectors 61,71 (see FIG. 4a), in thislatter instance, the securing bolts 17a" shown) mounted and secured onthe rear of the rear cross brace connector 71, at each lateral sideimmediately rearward of and fastened also to the pontoons 13(as byfastening to the keel flanges 13b), in which case a common rudder drive,such as a pulley and cable drive connection, may be employed inconjunction with a common steering unit such as a tiller or steeringwheel disposed within the cockpit 33. As such rudder arrangements do notgenerally form a part of 1 the present invention, such are notillustrated, particularly inasmuch as various different rudderarrangements may be suitably employed. In addition, as will be readilyapparent, some steering ability is obtainable by pivoting the motor Mupon its vertical support axis, and this motor-pivot steering action maybe used alone or in addition to the steering action of a separaterudder. or rudders such as generally described above.

While the invention has been illustrated and described in respect toseveral illustrative embodiments, it will be apparent to those skilledin the art that various modifications and improvements can be madewithout departing from the scope and spirit of the invention.Accordingly, the invention is not to be limited by the illustratedembodiments, but only by the scope of the appended claims.

That which is claimed is:

1. A watercraft comprising:

a pair of laterally spaced longitudinal pontoons,

a mid-hull secured to and carried between said pontoons and with itsbottom spaced above the flotation waterline of the total watercraft,

said mid-hull having a bottom wall with upstanding peripheral walls, theinterior surface of said bottom being inclined relative to the normalflotation waterline of said watercraft,

said mid-hull interior bottom surface being slanted in two directions,

said two directions forming an inverted generally crowned bottominterior,

and two self-bailing water discharge orifices in a wall of the mid-hullat the lowermost side zones of said inverted generally crowned bottominterior.

2. A watercraft comprising,

a hull having a bouyant water-engaging flotation section,

and longitudinally extending, laterally protruding,lateral-flow-restricting stabilization strip flanges disposed beneaththe normal waterline of said water-engaging flotation section,

said hull comprising two longitudinally extending, laterally spacedpontoons, each forming a bouyant water-engaging flotation section, andeach said flotation section having said longitudinally extendinglaterally protruding lateral-flow-restricting stabilization stripflanges disposed thereon,

said pontoons being substantially flat bottomed,

and said longitudinally extending stabilization strip flanges extendingfrom opposite sides of each of said pontoons adjacent said flat bottom,said stabilization strip flanges forming a lateral continuationextension of said flat bottom,

and further said longitudinally extending stabilization strip flangesextending from said opposite sides of said pontoons and spaced abovesaid bottom extension strip flanges.

3. A watercraft according to claim 2,

said further longitudinally extending stabilization strip flangescomprising dual purpose elastic bumper strips extending peripherallyalong said pontoons.

4. A watercraft according to claim 3, further comprising:

front and rear cross-brace connectors connecting between said pontoons,

said bumper strips extending also around the peripherally outer surfacesof said front and rear cross-brace connections.

5. A watercraft comprising,

a hull having a bouyant water-engaging flotation section,

and longitudinally extending, laterally protruding,lateral-flow-restricting stabilization strip flanges disposed beneaththe normal waterline of said water-engaging flotation section,

said hull comprising two longitudinally extending, laterally spacedpontoons, each forming a bouyant water-engaging flotation section, andeach said flotation section having said longitudinally extendinglaterally protruding lateral-flow-restricting stabilization stripflanges disposed thereon,

said pontoons being substantially flat bottomed,

and said longitudinally extending stabilization strip flanges extendingfrom opposite sides of each of said pontoons adjacent said flat bottom,said stabilization strip flanges forming a lateral continuationextension of said flat bottom,

and a vertical T-strip keel flange extending along the flat bottom ofeach of said pontoons and being adapted for joint attachment thereto ofa common hydrofoil,

said pontoons being interiorly vertically braced in the longitudinalzone thereof generally vertical aligned with said bottom keel stripflange.

6. A watercraft according to claim 5,

said pontoons having internal lateral, vertical, and longitudinalbracing with flotation foam therearound and therebetween.

7. A watercraft according to claim 6,

said internal lateral, vertical and longitudinal bracing comprising aplurality of longitudinally spaced T- braces, each formed of cross andinter-secured angle strips joined by an effectively common longitudinalvertical-bend-stiffing strip inter-secured thereto, and a surface skinsecured over and to each of said T-braces and longitudinal strip.

8. A watercraft according to claim 7,

said T-braces and effectively common longitudinal strip being weldedinto inter-secured relation at their respective junctions,

and the said T-braces being welded to said surface skin at at least amajor portion of their respective junctions.

9. A watercraft according to claim 8,

two cross-brace connectors connecting respectively across the front andrear of said pontoons, and spaced above the normal waterline of saidwatercraft,

and a mid-hull personnel-carrying cockpit section spaced from andbetween said cross-brace connectors and having its bottom disposed abovethe normal flotation waterline of said watercraft.

10. A watercraft according to claim 9,

the forward said cross-brace connector having a downwardly andrearwardly inclined lower surface spaced above the normal flotationwaterline of said watercraft.

11. A watercraft according to claim 10,

and a downwardly and rearwardly inclined propeller spray deflector platedisposed rearwardly of said mid-hull personnel-carrying cockpit sectionand between said cockpit section and said rear crossbrace connector.

12. A watercraft according to claim 11,

both of said cross-brace connectors having oppositely inclined lowersurfaces spaced above the normal ,water flotation waterline of saidwatercraft.

13. A watercraft according to claim 5,

said mid-hull cockpit section having a bottom with a plurality ofexterior longitudinally extending bracing stringer downwardly dependingstrip flanges disposed generally normal to and along the lower exteriorsurface of said bottom to provide longitudinal vertical-bend bracingwith minimum longitudinal water flow restriction and to enableunencumbered longitudinally brace-free bottom interior surfaceformation.

14. A watercraft according to claim 13,

said mid-hull cockpit section having a tapered forward nose section, andhaving a rearwardly, downwardly slanted bottom surface with an invertedgenerally crowned surface portion adjacent its rear end zone,

and gravity-flow water discharge self-bailers, one disposed at each rearcorner zone of said inverted crowned surface portion of said mid-hullcockpit section and above the normal flotation waterline of saidwatercraft.

15. A watercraft comprising:

a mid-hull cockpit secured to and suspended between a pair of flotationpontoons and above the normal flotation waterline thereof throughlateral cockpit-to-pontoon connection means,

and two cross-brace connectors additional to the structure of saidcockpit and additional to said lateral cockpit-to-pontoon connectionmeans connecting respectively across the front and rear ends of saidpontoons and spaced above the normal waterline of said watercraft andmovable below the waterline and into engagement with the water uponrespective forward or rearward pitching of the watercraft, and beingspaced forwardly and rearwardly respectively of said mid-hull cockpit.

16. A watercraft according to claim 15,

said cross-brace connectors having oppositely inclined lower surfaces.

17. A watercraft comprising,

a mid-hull cockpit secured to and suspended between a pair of flotationpontoons and above the normal flotation waterline thereof,

and two cross-brace connectors connecting respectively across the frontand rear of said pontoons and spaced above the normal waterline of saidwatercraft,

said cross-brace connectors inclined lower surfaces,

and a downwardly and rearwardly inclined propeller spray deflectordisposed rearwardly of said midhaving oppositely hull cockpit, andbetween said mid-hull cockpit and said rear cross brace connector,

said propeller spray deflector being spaced from the rear of saidmid-hull cockpit.

18. A watercraft according to claim 17,

said mid-hull cockpit having a bottom with a plurality of exteriorlongitudinally extending bracing stringer strip flanges disposedgenerally normally to and along the lower exterior surface of saidbottom to provide longitudinal bracing with minimum longitudinal waterflow restriction and to enable unencumbered longitudinally brace-freebottom interior surface formation.

19. A watercraft according to claim 18,

said mid-hull cockpit having a rearwardly downwardly slanted interiordeck surface,

and gravity-flow self-bailing water discharge orifices, one disposed ateach of the rear corner zones of said mid-hull cockpit and above thenormal flotation waterline of said watercraft.

20. A watercraft comprising,

a mid-hull cockpit secured to and suspended between a pair of flotationpontoons and above the normal flotation waterline thereof,

and two cross-brace connectors connecting respectively across the frontand rear of said pontoons and spaced above the normal waterline of saidwatercraft,

and a downwardly and rearwardly inclined spray deflector secured betweensaid pontoons and disposed in spaced relation rearwardly of said midhullcockpit, said spray deflector comprising a pivoted plate pivotallysecured at its rear end zone to said rear cross-brace-connector, thepivot line therefor extending along the lower rear edge of saiddeflector.

21. A watercraft comprising,

a mid-hull cockpit secured to and suspended between a pair of flotationpontoons and above the normal flotation waterline thereof,

and a cross-brace connector connecting across the rear of said pontoonsand spaced above the normal waterline 'of said watercraft,

and a downwardly and rearwardly inclined propeller spray deflectordisposed rearwardly of said midhull cockpit, and between said mid-hullcockpit and said rear cross brace connector,

said propeller spray deflector being spaced from the rear of saidmid-hull cockpit.

22. A watercraft comprising,

a mid-hull cockpit secured to and suspended between a pair of flotationpontoons and above the normal flotation waterline thereof throughlateral cockpit-to-pontoon connection means,

and two cross-brace connectors additional to the structure of saidcockpit and additional to said lateral cockpit-to-pontoon connectionmeans and connection respectively across the front and rear ends of saidpontoons and spaced above the normal waterline of said watercraft andmovable below the waterline and into engagement with the water uponrespective forward or rearward pitching of the watercraft,

said cross-brace connectors having respectively forwardly and rearwardlyextending oppositely inclined lower surfaces.

1. A watercraft comprising: a pair of laterally spaced longitudinalpontoons, a mid-hull secured to and carried between said pontoons andwith its bottom spaced above the flotation waterline of the totalwatercraft, said mid-hull having a bottom wall with upstandingperipheral walls, the interior surface of said bottom being inclinedrelative to the normal flotation waterline of said watercraft, saidmid-hull interior bottom surface being slanted in two directions, saidtwo directions forming an inverted generally crowned bottom interior,and two self-bailing water discharge orifices in a wall of the mid-hullat the lowermost side zones of said inverted generally crowned bottominterior.
 2. A watercraft comprising, a hull having a bouyantwater-engaging flotation section, and longitudinally extending,laterally protruding, lateral-flow-restricting stabilization stripflanges disposed beneath the normal waterline of said water-engagingflotation section, said hull comprising two longitudinally extending,laterally spaced pontoons, each forming a bouyant water-engagingflotation section, and each said flotation section having saidlongitudinally extending laterally protruding lateral-flow-restrictingstabilization strip flanges disposed thereon, said pontoons beingsubstantially flat bottomed, and said longitudinally extendingstabilization strip flanges extending from opposite sides of each ofsaid pontoons adjacent said flat bottom, said stabilization stripflanges forming a lateral continuation extension of said flat bottom,and further said longitudinally extending stabilization strip flangesextending from said opposite sides of said pontoons and spaced abovesaid bottom extension strip flanges.
 3. A watercraft according to claim2, said further longitudinally extending stabilization strip flangescomprising dual purpose elastic bumper strips extending peripherallyalong said pontoons.
 4. A watercraft according to claim 3, furthercomprising: front and rear cross-brace connectors connecting betweensaid pontoons, said bumper strips extending also around the peripherallyouter surfaces of said front and rear cross-brace connections.
 5. Awatercraft comprising, a hull having a bouyant water-engaging flotationsection, and longitudinally extending, laterally protruding,lateral-flow-restricting stabilization strip flanges disposed beneaththe normal waterline of said water-engaging flotation section, said hullcomprising two longitudinally extending, laterally spaced pontoons, eachforming a bouyant water-engaging flotation section, and each saidflotation section having said longitudinally extending laterallyprotruding lateral-flow-restricting stabilization strip flanges disposedthereon, said pontoons being substantially flat bottomed, anD saidlongitudinally extending stabilization strip flanges extending fromopposite sides of each of said pontoons adjacent said flat bottom, saidstabilization strip flanges forming a lateral continuation extension ofsaid flat bottom, and a vertical T-strip keel flange extending along theflat bottom of each of said pontoons and being adapted for jointattachment thereto of a common hydrofoil, said pontoons being interiorlyvertically braced in the longitudinal zone thereof generally verticalaligned with said bottom keel strip flange.
 6. A watercraft according toclaim 5, said pontoons having internal lateral, vertical, andlongitudinal bracing with flotation foam therearound and therebetween.7. A watercraft according to claim 6, said internal lateral, verticaland longitudinal bracing comprising a plurality of longitudinally spacedT-braces, each formed of cross and inter-secured angle strips joined byan effectively common longitudinal vertical-bend-stiffing stripinter-secured thereto, and a surface skin secured over and to each ofsaid T-braces and longitudinal strip.
 8. A watercraft according to claim7, said T-braces and effectively common longitudinal strip being weldedinto inter-secured relation at their respective junctions, and the saidT-braces being welded to said surface skin at at least a major portionof their respective junctions.
 9. A watercraft according to claim 8, twocross-brace connectors connecting respectively across the front and rearof said pontoons, and spaced above the normal waterline of saidwatercraft, and a mid-hull personnel-carrying cockpit section spacedfrom and between said cross-brace connectors and having its bottomdisposed above the normal flotation waterline of said watercraft.
 10. Awatercraft according to claim 9, the forward said cross-brace connectorhaving a downwardly and rearwardly inclined lower surface spaced abovethe normal flotation waterline of said watercraft.
 11. A watercraftaccording to claim 10, and a downwardly and rearwardly inclinedpropeller spray deflector plate disposed rearwardly of said mid-hullpersonnel-carrying cockpit section and between said cockpit section andsaid rear cross-brace connector.
 12. A watercraft according to claim 11,both of said cross-brace connectors having oppositely inclined lowersurfaces spaced above the normal water flotation waterline of saidwatercraft.
 13. A watercraft according to claim 5, said mid-hull cockpitsection having a bottom with a plurality of exterior longitudinallyextending bracing stringer downwardly depending strip flanges disposedgenerally normal to and along the lower exterior surface of said bottomto provide longitudinal vertical-bend bracing with minimum longitudinalwater flow restriction and to enable unencumbered longitudinallybrace-free bottom interior surface formation.
 14. A watercraft accordingto claim 13, said mid-hull cockpit section having a tapered forward nosesection, and having a rearwardly, downwardly slanted bottom surface withan inverted generally crowned surface portion adjacent its rear endzone, and gravity-flow water discharge self-bailers, one disposed ateach rear corner zone of said inverted crowned surface portion of saidmid-hull cockpit section and above the normal flotation waterline ofsaid watercraft.
 15. A watercraft comprising: a mid-hull cockpit securedto and suspended between a pair of flotation pontoons and above thenormal flotation waterline thereof through lateral cockpit-to-pontoonconnection means, and two cross-brace connectors additional to thestructure of said cockpit and additional to said lateralcockpit-to-pontoon connection means connecting respectively across thefront and rear ends of said pontoons and spaced above the normalwaterline of said watercraft and movable below the waterline and intoengagement with the water upon respective forward or rearward pitchingof the watercraft, aNd being spaced forwardly and rearwardlyrespectively of said mid-hull cockpit.
 16. A watercraft according toclaim 15, said cross-brace connectors having oppositely inclined lowersurfaces.
 17. A watercraft comprising, a mid-hull cockpit secured to andsuspended between a pair of flotation pontoons and above the normalflotation waterline thereof, and two cross-brace connectors connectingrespectively across the front and rear of said pontoons and spaced abovethe normal waterline of said watercraft, said cross-brace connectorshaving oppositely inclined lower surfaces, and a downwardly andrearwardly inclined propeller spray deflector disposed rearwardly ofsaid mid-hull cockpit, and between said mid-hull cockpit and said rearcross brace connector, said propeller spray deflector being spaced fromthe rear of said mid-hull cockpit.
 18. A watercraft according to claim17, said mid-hull cockpit having a bottom with a plurality of exteriorlongitudinally extending bracing stringer strip flanges disposedgenerally normally to and along the lower exterior surface of saidbottom to provide longitudinal bracing with minimum longitudinal waterflow restriction and to enable unencumbered longitudinally brace-freebottom interior surface formation.
 19. A watercraft according to claim18, said mid-hull cockpit having a rearwardly downwardly slantedinterior deck surface, and gravity-flow self-bailing water dischargeorifices, one disposed at each of the rear corner zones of said mid-hullcockpit and above the normal flotation waterline of said watercraft. 20.A watercraft comprising, a mid-hull cockpit secured to and suspendedbetween a pair of flotation pontoons and above the normal flotationwaterline thereof, and two cross-brace connectors connectingrespectively across the front and rear of said pontoons and spaced abovethe normal waterline of said watercraft, and a downwardly and rearwardlyinclined spray deflector secured between said pontoons and disposed inspaced relation rearwardly of said mid-hull cockpit, said spraydeflector comprising a pivoted plate pivotally secured at its rear endzone to said rear cross-brace-connector, the pivot line thereforextending along the lower rear edge of said deflector.
 21. A watercraftcomprising, a mid-hull cockpit secured to and suspended between a pairof flotation pontoons and above the normal flotation waterline thereof,and a cross-brace connector connecting across the rear of said pontoonsand spaced above the normal waterline of said watercraft, and adownwardly and rearwardly inclined propeller spray deflector disposedrearwardly of said mid-hull cockpit, and between said mid-hull cockpitand said rear cross brace connector, said propeller spray deflectorbeing spaced from the rear of said mid-hull cockpit.
 22. A watercraftcomprising, a mid-hull cockpit secured to and suspended between a pairof flotation pontoons and above the normal flotation waterline thereofthrough lateral cockpit-to-pontoon connection means, and two cross-braceconnectors additional to the structure of said cockpit and additional tosaid lateral cockpit-to-pontoon connection means and connectionrespectively across the front and rear ends of said pontoons and spacedabove the normal waterline of said watercraft and movable below thewaterline and into engagement with the water upon respective forward orrearward pitching of the watercraft, said cross-brace connectors havingrespectively forwardly and rearwardly extending oppositely inclinedlower surfaces.